（1. Company Office, Hangzhou Iron and Steel Group Co., Ltd., Hangzhou 310022, Zhejiang, China 2. Manufacturing Management Department, Ningbo Iron and Steel Co., Ltd., Ningbo 315807, Zhejiang, China）
Abstract：The microstructure transformations of the dual phase steel DP600 with Mo in different cooling modes, transition temperatures and cooling rates were studied by thermal simulation experiments. The proportions of martensite and the grain size levels were analyzed after phase transition, and the production process of DP600 was designed on the basis of the experiments, while the influence of Mo element on dual phase steel was also discussed. The results showed that the martensite formed by the two- stage cooling process was smaller than that by the one- stage process, and the grain size was improved one level after the change of hot rolling microstructure was finished for DP600 steel. There was a good phase transition balance temperature in the process of transformation from austenite to ferrite. Reducing the overcooling transition rate of ferrite and pearlite in the DP600 steel over the temperature of 590 ℃ would refine grain size and increase the proportion of martensite. The microstructure of the DP600 steel obtained by production was ferrite and martensite. Meanwhile, the martensitic ratio was 17% and the grain size was 11 level. The tensile strength in vertical and horizontal direction was 592 and 620 MPa, respectively, and the elongation was 28.5% and 26.5%, respectively. The Mo element could strongly inhibit the transformation of ferritic and reduce the ferrite transition zone for the C- Si- Mn- Cr- Mo DP600 steel.
殳黎平，朱施利，胡文豪，骆仁智，丘祥光，邬晓燕. 含钼双相钢DP600相变研究和工艺实践[J]. 中国冶金, 2018, 28(6): 43-47.
SHU Li- ping,ZHU Shi- li,HU Wen- hao,LUO Ren- zhi,QIU Xiang- guang,WU Xiao- yan. Research of phase transition and process practice on DP600 dual phase steel with molybdenum[J]. China Metallurgy, 2018, 28(6): 43-47.
2018, Vol. 28 
